One of the most unpleasant, but seemingly almost unavoidable mishaps in using a motor vehicle or boat or other engine powered apparatus is that, on occasion, there is insufficient electrical power left in the rechargeable (starting) battery to start the engine. Such eventualities may be caused by lack of attention of the operator, age of the battery, failure of the charging system, ambient conditions, leaving lights or other power consuming devices on, or numerous other factors. The problem is particularly pervasive in cold climates, and affects literally thousands of engine starting applications, particularly in recreational or seasonal use devices.
Similar problems also affect devices other than motor vehicles. For example, emergency generators are often battery started, and cannot be conveniently started when the battery is dead, particularly if the engine was unused for a period of time and the battery charge was depleted. This is of particular concern in applications where the rapid and reliable starting of the generator is critical, such as hospitals, communications backup, and military generators.
Inability to start an engine can have relatively high costs. For example, pilots frequently fly into airports or remote grass strips where no auxiliary power is available, and sometimes become stranded if the on-board battery fails. Boaters also find themselves caught with dead batteries in locations where it may be impossible to easily "jump start" their engines. Automobile motorists also often become stranded with dead batteries in their vehicles, often at very inconvenient times and locations, particularly in cold weather situations, where the battery performance is degraded.
There are basically four classes of devices available for emergency starting of automobiles, airplanes, boats, generators and other apparatus using internal combustion engines. Unfortunately, all such devices tend to be quite cumbersome to use.
Perhaps the most widely used class of emergency starting apparatus is characterized by simple jumper cables. Jumper cables typically comprise two insulated wires, about 6 to 20 feet long, which are capable of carrying upwards of 200 Amps for short periods of time. Clamps or clips are generally connected to the ends of the wires to aid in securing electrical contact with battery terminals and "ground" points on the apparatus being started. Known jumper cables are advantageous in being relatively inexpensive and readily configurable for convenient storage, but they suffer from several disadvantages as well. Among other things, jumper cables require a second outside power source, such as the battery of a running automobile or other vehicle, to provide the energy delivered to the battery being jumped. That requirement is of critical importance when another vehicle is unavailable, and also when another vehicle is available, but cannot be positioned close enough for the jumper cables to connect the respective batteries. Still further, jumper cables are problematic, and even dangerous, in requiring the proper connection of four connectors. Improper connection can result in dangerous sparks or even explosions, if volatile fumes are ignited by sparks.
Another class of emergency starting apparatus is characterized by battery start carts. These are wheeled vehicles containing a large capacity battery, or bank of batteries, electrically coupled to high capacity electrically conducting cables. Depending on the anticipated usage, the cables may have either general-purpose clamps or specialized end-mounted connectors. Small start carts mounted on hand truck frames are familiar features in used and new automobile car dealerships, while larger, motor vehicle sized start carts are commonly used in airports to start airplanes. The batteries in portable start carts are generally recharged using line current at a recharging station, although they may also carry their own recharging power source, i.e. gasoline powered generator. The major advantages of start carts are their mobility and relatively high electrical storage capacity, allowing them to provide numerous "jump starts" without recharging.
A major disadvantage, however, is that start carts are inherently too bulky and heavy to be generally carried about in motor vehicles, boats, motorcycles, or other applications. They are also usually more costly than basic portable battery packs.
Another class of emergency starting apparatus is characterized by high powered battery chargers, capable of providing sufficient power to quickly recharge storage batteries, and to augment the battery output power for engine starting. Known high powered charger/boosters are typically devices measuring about 12-24 inches in each dimension, and are usually portable, or have wheels. Unfortunately, they require an outside power source such as line current from a standard household electrical outlet plug. Smaller chargers are available, but typically have relatively low charging rates, and therefore require several hours to recharge a battery with sufficient energy to be used in starting a motor. Such smaller chargers do not have sufficient energy to start most engines by themselves.
A forth class of devices includes portable battery packs with integrated cables, designed to be carried onboard one's vehicle for use when the primary starting battery is depleted and unusable. These portable battery packs are convenient and functional, but somewhat bulky and heavy (typically 15-25 pounds). The cables attached to the battery pack housing are each generally about 12-18" long, so they can be conveniently wrapped around the battery housing and clamped in a safe position to minimize short circuiting them.
Virtually all external auxiliary power devices have one common problem--the liklihood of improper connection to the battery being "jumped", or short circuiting the leads/clamps producing sparks and possible serious damage or fires. This shortcoming has been a concern of potential inexperienced users, especially women who don't like to have to try to make connections under the hood of vehicles, particularly in the dark!
Thus, there is a continuing need to provide improved methods and apparatus that supply independent electrical power for starting engines.